1 /* gras/datadesc.h - Describing the data you want to exchange */
3 /* Copyright (c) 2004, 2005, 2006, 2007, 2009, 2010. The SimGrid Team.
4 * All rights reserved. */
6 /* This program is free software; you can redistribute it and/or modify it
7 * under the terms of the license (GNU LGPL) which comes with this package. */
9 #ifndef GRAS_DATADESC_H
10 #define GRAS_DATADESC_H
12 #include "xbt/misc.h" /* SG_BEGIN_DECL */
13 #include "xbt/dynar.h" /* void_f_pvoid_t */
17 /** @addtogroup GRAS_dd Data description
18 * @brief Describing data to be exchanged
20 * Since GRAS takes care of potential representation conversion when the platform is heterogeneous,
21 * any data which transits on the network must be described beforehand.
23 * There is several possible interfaces for this, ranging from the really completely automatic parsing to
24 * completely manual. Let's study each of them from the simplest to the more advanced:
26 * - Section \ref GRAS_dd_basic presents how to retrieve and use an already described type.
27 * - Section \ref GRAS_dd_auto shows how to get GRAS parsing your type description automagically. This
28 * is unfortunately not always possible (only works for some structures), but if it is for your data,
29 * this is definitly the way to go.
30 * - Section \ref GRAS_dd_manual presents how to build a description manually. This is useful when you want
31 * to describe an array or a pointer of pre-defined structures.
32 * - You sometimes need to exchange informations between descriptions at send or receive time. This is
33 * for example useful when your structure contains an array which size is given by another field of the
35 * - Section \ref GRAS_dd_cb_simple provides a simple interface to do so, allowing to share integers stored on a stack.
36 * - Section \ref GRAS_dd_cb_full provides a full featured interface to do so, but it may reveal somehow difficult to use.
38 /** @defgroup GRAS_dd_basic Basic operations on data descriptions
40 * \htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Basics" --> \endhtmlonly
42 * If you only want to send pre-existing types, simply retrieve the pre-defined description with
43 * the \ref gras_datadesc_by_name function. Existing types entail:
44 * - char (both signed and unsigned)
45 * - int (short, regular, long and long long, both signed and unsigned)
47 * - string (which is indeed a reference to a dynamically sized array of char, strlen being used to retrieve the size)
49 * Example:\verbatim gras_datadesc_type_t i = gras_datadesc_by_name("int");
50 gras_datadesc_type_t uc = gras_datadesc_by_name("unsigned char");
51 gras_datadesc_type_t str = gras_datadesc_by_name("string");\endverbatim
55 /** @brief Opaque type describing a type description. */
56 typedef struct s_gras_datadesc_type *gras_datadesc_type_t;
58 /** \brief Search a type description from its name */
59 XBT_PUBLIC(gras_datadesc_type_t) gras_datadesc_by_name(const char *name);
60 XBT_PUBLIC(gras_datadesc_type_t) gras_datadesc_by_name_or_null(const char
65 /** @defgroup GRAS_dd_auto Automatic parsing of data descriptions
67 * \htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Automatic parsing" --> \endhtmlonly
69 * If you need to declare a new datatype, this is the simplest way to describe it to GRAS. Simply
70 * enclose its type definition into a \ref GRAS_DEFINE_TYPE macro call, and you're set. Here is
71 * an type declaration example: \verbatim GRAS_DEFINE_TYPE(mytype,struct mytype {
75 * The type is then both copied verbatim into your source file and stored for further parsing. This allows
76 * you to let GRAS parse the exact version you are actually using in your program.
77 * You can then retrieve the corresponding type description with \ref gras_datadesc_by_symbol.
78 * Don't worry too much for the performances, the type is only parsed once and a binary representation
79 * is stored and used in any subsequent calls.
81 * If your structure contains any pointer, you have to explain GRAS the size of the pointed array. This
82 * can be 1 in the case of simple references, or more in the case of regular arrays. For that, use the
83 * \ref GRAS_ANNOTE macro within the type declaration you are passing to \ref GRAS_DEFINE_TYPE. This macro
84 * rewrites itself to nothing in the declaration (so they won't pollute the type definition copied verbatim
85 * into your code), and give some information to GRAS about your pointer.
87 * GRAS_ANNOTE takes two arguments being the key name and the key value. For now, the only accepted key name
88 * is "size", to specify the length of the pointed array. It can either be:
89 * - the string "1" (without the quote),
90 * - the name of another field of the structure
91 * - a sort of computed expression for multidimensional arrays (see below -- pay attention to the warnings below).
93 * Here is an example:\verbatim GRAS_DEFINE_TYPE(s_clause,
96 struct s_array *father GRAS_ANNOTE(size,1);
98 int *data GRAS_ANNOTE(size,length);
101 int *matrix GRAS_ANNOTE(size,rows*cols);
104 * It specifies that the structure s_array contains six fields, that the \a name field is a classical null-terminated
105 * char* string (#xbt_string_t is just an helper type defined exactly to help the parsing macro to specify the semantic of the pointer),
106 * that \a father field is a simple reference, that the size of the array pointed by \a data is the \a length field, and that the
107 * \a matrix field is an arraywhich size is the result of \a rows times \a cols.
109 * \warning Since GRAS_DEFINE_TYPE is a macro, you shouldn't put any comma in your type definition
110 * (comma separates macro args). For example, change \verbatim int a, b;\endverbatim to \verbatim int a;
113 * \section gras_dd_define \#define and fixed size array
115 * If you want to exchange arrays which size is given at compilation time by a
116 * \#defined constant, you need to keep GRAS informed. It would be done the
119 \verbatim #define BLOCK_SIZE 32
120 GRAS_DEFINE_TYPE(s_toto,
122 double data[BLOCK_SIZE];
125 void register_messages() {
126 gras_datadesc_type_t toto_type;
128 gras_datadesc_set_const("BLOCK_SIZE",BLOCK_SIZE);
129 toto_type = gras_datadesc_by_symbol(s_toto);
132 * The form <tt>gras_datadesc_set_const("BLOCK_SIZE",BLOCK_SIZE);</tt> ensures
133 * that when you change the definition of the constant, GRAS keeps informed of
134 * the right value. Passing the numerical value of the constant as second
135 * argument would be a bad idea to that regard. Of course, the call to
136 * gras_datadesc_set_const() should come before any gras_datadesc_by_symbol()
137 * containing references to it.
139 * \section GRAS_dd_multidim Defining multidimentional arrays
141 * The mecanism for multidimensional arrays is known to be fragile and cumbersome. If you want to use it,
142 * you have to understand how it is implemented: the multiplication is performed using the sizes stack. In previous example,
143 * a \ref gras_datadesc_cb_push_int callback is added to the \a rows field and a \ref gras_datadesc_cb_push_int_mult one is
144 * added to \a cols. So, when the structure is sent, the \a rows field push its value onto the stack, then the \a cols field
145 * retrieve this value from the stack, compute (and push) the multiplication value. The \a matrix field can then retrieve this
146 * value by poping the array. There is several ways for this to go wrong:
147 * - if the matrix field is placed before the sizes, the right value won't get pushed into the stack soon enough.
148 * Reorder your structure fields if needed.
149 * - if you write GRAS_ANNOTE(size,cols*rows); in previous example (inverting rows and cols in annotation),
150 * \a rows will be given a \ref gras_datadesc_cb_push_int_mult. This cannot work since it will try to
151 * pop the value which will be pushed by \a cols <i>afterward</i>.
152 * - if you have more than one matrix in your structure, don't interleave the size. They are pushed/poped in the structure order.
153 * - if some of the sizes are used in more than one matrix, you cannot use this mecanism -- sorry.
155 * If you cannot express your datadescs with this mechanism, you'll have to use the more advanced
156 * (and somehow complex) one described in the \ref GRAS_dd_cb_full.
158 * \section GRAS_dd_multifile Projects spanning over multiple files
160 * GRAS_DEFINE_TYPE declares some symbols to work, it needs some special
161 * care when used in several files. In such case, you want the regular type
162 * definition in all files, but the gras specific symbol defined in only
163 * one file. For example, consider the following gras project sketch.
165 \verbatim #include <gras.h>
167 GRAS_DEFINE_TYPE(my_type,struct my_type {
173 int client(int argc, char *argv[]) {
177 int server(int argc, char *argv[]) {
181 * If you want to split this in two files (one for each kind of processes),
182 * you need to put the GRAS_DEFINE_TYPE block in a separate header (so that
183 * each process kind see the associated C type definition). But
184 * then you cannot include this right away in all files because the extra
185 * symbols containing the GRAS definition would be dupplicated.
187 * You thus have to decide in which C file the symbols will live. In that
188 * file, include the header without restriction:
190 \verbatim #include "my_header.h"
192 int client(int argc, char *argv[]) {
196 * And in the other files needing the C definitions without the extra GRAS
197 * symbols, declare the symbol GRAS_DEFINE_TYPE_EXTERN before loading gras.h:
199 \verbatim #define GRAS_DEFINE_TYPE_EXTERN
201 #include "my_header.h"
203 int server(int argc, char *argv[]) {
208 * Sometimes, the situation is even more complicated: There is some shared
209 * messages that you want to see from every file, and some private messages
210 * that you want to be defined only in one C file.
211 * In that case, use the previous trick for common messages, and use
212 * #GRAS_DEFINE_TYPE_LOCAL for the private messages.
214 * For now, there is no way to have semi-private symbols (for example shared
215 * in all files of a library), sorry. Use functions as interface to your
216 * library instead of publishing directly the messages.
222 /** @brief Automatically parse C code
225 #define GRAS_DEFINE_TYPE(name,def) \
226 const char * _gras_this_type_symbol_does_not_exist__##name=#def; def
228 #ifndef DOXYGEN_SKIP /* doxygen don't like macro fun too much */
229 # ifdef GRAS_DEFINE_TYPE_EXTERN
230 # undef GRAS_DEFINE_TYPE
231 # define GRAS_DEFINE_TYPE(name,def) def
232 # undef GRAS_DEFINE_TYPE_EXTERN
236 /** @brief if this symbol is defined, the \a GRAS_DEFINE_TYPE symbols live in another file.
239 #define GRAS_DEFINE_TYPE_EXTERN 1
240 /* leave the fun of declaring this to the user */
241 #undef GRAS_DEFINE_TYPE_EXTERN
243 /** @brief Define a symbol to be automatically parsed, disregarding #GRAS_DEFINE_TYPE_EXTERN
246 * Call this macro instead of #GRAS_DEFINE_TYPE if you had to define #GRAS_DEFINE_TYPE_EXTERN
247 * to load some external symbols, but if you now want to automatically parse the content of
248 * your private messages.
250 #define GRAS_DEFINE_TYPE_LOCAL(name, def) \
251 const char * _gras_this_type_symbol_does_not_exist__##name=#def; def
253 /** @brief Retrieve a datadesc which was previously parsed
256 #define gras_datadesc_by_symbol(name) \
257 (gras_datadesc_by_name_or_null(#name) ? \
258 gras_datadesc_by_name_or_null(#name) : \
259 gras_datadesc_parse(#name, \
260 _gras_this_type_symbol_does_not_exist__##name) \
264 * @brief Add an annotation to a type to be automatically parsed
266 #define GRAS_ANNOTE(key,val)
268 /** @brief Defines the value of a define to the datatype parsing infrastructure
270 XBT_PUBLIC(void) gras_datadesc_set_const(const char *name, int value);
274 XBT_PUBLIC(gras_datadesc_type_t)
275 gras_datadesc_parse(const char *name, const char *C_statement);
277 /** @defgroup GRAS_dd_manual Simple manual data description
280 * Here are the functions to use if you want to declare your description manually.
281 * The function names should be self-explanatory in most cases.
283 * You can add callbacks to the datatypes doing any kind of action you may want. Usually,
284 * pre-send callbacks are used to prepare the type expedition while post-receive callbacks
285 * are used to fix any issue after the receive.
287 * If your types are dynamic, you'll need to add some extra callback. For example, there is a
288 * specific callback for the string type which is in charge of computing the length of the char
289 * array. This is done with the cbps mechanism, explained in next section.
291 * If your types may contain pointer cycle, you must specify it to GRAS using the @ref gras_datadesc_cycle_set.
296 unsigned long int l1;
298 unsigned long int l2;
301 my_type=gras_datadesc_struct("mystruct");
302 gras_datadesc_struct_append(my_type,"c1", gras_datadesc_by_name("unsigned char"));
303 gras_datadesc_struct_append(my_type,"l1", gras_datadesc_by_name("unsigned long"));
304 gras_datadesc_struct_append(my_type,"c2", gras_datadesc_by_name("unsigned char"));
305 gras_datadesc_struct_append(my_type,"l2", gras_datadesc_by_name("unsigned long int"));
306 gras_datadesc_struct_close(my_type);
308 my_type=gras_datadesc_ref("mystruct*", gras_datadesc_by_name("mystruct"));
310 [Use my_type to send pointers to mystruct data]\endverbatim
315 /** \brief Opaque type describing a type description callback persistant state. */
316 typedef struct s_gras_cbps *gras_cbps_t;
318 /* callbacks prototypes */
319 /** \brief Prototype of type callbacks returning nothing. */
320 typedef void (*gras_datadesc_type_cb_void_t) (gras_datadesc_type_t
321 typedesc, gras_cbps_t vars,
323 /** \brief Prototype of type callbacks returning an int. */
324 typedef int (*gras_datadesc_type_cb_int_t) (gras_datadesc_type_t
325 typedesc, gras_cbps_t vars,
327 /** \brief Prototype of type callbacks selecting a type. */
334 gras_datadesc_type_t(*gras_datadesc_selector_t) (gras_datadesc_type_t
340 /******************************************
341 **** Declare datadescription yourself ****
342 ******************************************/
344 XBT_PUBLIC(gras_datadesc_type_t) gras_datadesc_struct(const char *name);
345 XBT_PUBLIC(void) gras_datadesc_struct_append(gras_datadesc_type_t
346 struct_type, const char *name,
349 XBT_PUBLIC(void) gras_datadesc_struct_close(gras_datadesc_type_t
353 XBT_PUBLIC(gras_datadesc_type_t) gras_datadesc_union(const char *name,
354 gras_datadesc_type_cb_int_t
356 XBT_PUBLIC(void) gras_datadesc_union_append(gras_datadesc_type_t
357 union_type, const char *name,
360 XBT_PUBLIC(void) gras_datadesc_union_close(gras_datadesc_type_t
364 XBT_PUBLIC(gras_datadesc_type_t)
365 gras_datadesc_ref(const char *name, gras_datadesc_type_t referenced_type);
366 XBT_PUBLIC(gras_datadesc_type_t)
367 gras_datadesc_copy(const char *name, gras_datadesc_type_t copied_type);
368 XBT_PUBLIC(gras_datadesc_type_t)
369 gras_datadesc_ref_generic(const char *name,
370 gras_datadesc_selector_t selector);
372 XBT_PUBLIC(gras_datadesc_type_t)
373 gras_datadesc_array_fixed(const char *name,
374 gras_datadesc_type_t element_type,
375 long int fixed_size);
376 XBT_PUBLIC(gras_datadesc_type_t)
377 gras_datadesc_array_dyn(const char *name,
378 gras_datadesc_type_t element_type,
379 gras_datadesc_type_cb_int_t dynamic_size);
380 XBT_PUBLIC(gras_datadesc_type_t)
381 gras_datadesc_ref_pop_arr(gras_datadesc_type_t element_type);
383 XBT_PUBLIC(gras_datadesc_type_t)
384 gras_datadesc_dynar(gras_datadesc_type_t elm_t, void_f_pvoid_t free_func);
385 XBT_PUBLIC(gras_datadesc_type_t)
386 gras_datadesc_matrix(gras_datadesc_type_t elm_t,
387 void_f_pvoid_t const free_f);
389 /*********************************
390 * Change stuff within datadescs *
391 *********************************/
393 /** \brief Specify that this type may contain cycles */
394 XBT_PUBLIC(void) gras_datadesc_cycle_set(gras_datadesc_type_t type);
395 /** \brief Specify that this type do not contain any cycles (default) */
396 XBT_PUBLIC(void) gras_datadesc_cycle_unset(gras_datadesc_type_t type);
397 /** \brief Add a pre-send callback to this datadesc. */
398 XBT_PUBLIC(void) gras_datadesc_cb_send(gras_datadesc_type_t type,
399 gras_datadesc_type_cb_void_t pre);
400 /** \brief Add a post-receive callback to this datadesc.*/
401 XBT_PUBLIC(void) gras_datadesc_cb_recv(gras_datadesc_type_t type,
402 gras_datadesc_type_cb_void_t post);
403 /** \brief Add a pre-send callback to the given field of the datadesc */
404 XBT_PUBLIC(void) gras_datadesc_cb_field_send(gras_datadesc_type_t type,
405 const char *field_name,
406 gras_datadesc_type_cb_void_t
408 /** \brief Add a post-receive callback to the given field of the datadesc */
409 XBT_PUBLIC(void) gras_datadesc_cb_field_recv(gras_datadesc_type_t type,
410 const char *field_name,
411 gras_datadesc_type_cb_void_t
413 /** \brief Add a pre-send callback to the given field resulting in its value to be pushed */
414 XBT_PUBLIC(void) gras_datadesc_cb_field_push(gras_datadesc_type_t type,
415 const char *field_name);
416 /** \brief Add a pre-send callback to the given field resulting in its value multiplied to any previously pushed value and then pushed back */
418 gras_datadesc_cb_field_push_multiplier(gras_datadesc_type_t type,
422 /******************************
423 * Get stuff within datadescs *
424 ******************************/
425 /** \brief Returns the name of a datadescription */
426 XBT_PUBLIC(const char *) gras_datadesc_get_name(gras_datadesc_type_t ddt);
427 /** \brief Returns the identifier of a datadescription */
428 XBT_PUBLIC(int) gras_datadesc_get_id(gras_datadesc_type_t ddt);
432 /** @defgroup GRAS_dd_cb_simple Data description with Callback Persistant State: Simple push/pop mechanism
435 * Sometimes, one of the callbacks need to leave information for the next ones. If this is a simple integer (such as
436 * an array size), you can use the functions described here. If not, you'll have to play with the complete cbps interface.
438 * \htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Simple push/pop Callback State" -->\endhtmlonly
440 * Here is an example:\verbatim
446 my_type=gras_datadesc_struct("s_array");
447 gras_datadesc_struct_append(my_type,"length", gras_datadesc_by_name("int"));
448 gras_datadesc_cb_field_send (my_type, "length", gras_datadesc_cb_push_int);
450 gras_datadesc_struct_append(my_type,"data",
451 gras_datadesc_array_dyn ("s_array::data",gras_datadesc_by_name("int"), gras_datadesc_cb_pop));
452 gras_datadesc_struct_close(my_type);
456 * The *_mult versions are intended for multi-dimensional arrays: They multiply their value to the previously pushed one
457 * (by another field callback) and push the result of the multiplication back. An example of use follows. Please note
458 * that the first field needs a regular push callback, not a multiplier one. Think of it as a stacked calculator (man dc(1)).\verbatim
465 my_type=gras_datadesc_struct("s_matrix");
466 gras_datadesc_struct_append(my_type,"row", gras_datadesc_by_name("int"));
467 gras_datadesc_cb_field_send (my_type, "length", gras_datadesc_cb_push_int);
468 gras_datadesc_struct_append(my_type,"col", gras_datadesc_by_name("int"));
469 gras_datadesc_cb_field_send (my_type, "length", gras_datadesc_cb_push_int_mult);
471 gras_datadesc_struct_append(my_type,"data",
472 gras_datadesc_array_dyn ("s_matrix::data",gras_datadesc_by_name("int"), gras_datadesc_cb_pop));
473 gras_datadesc_struct_close(my_type);
479 XBT_PUBLIC(void) gras_cbps_i_push(gras_cbps_t ps, int val);
480 XBT_PUBLIC(int) gras_cbps_i_pop(gras_cbps_t ps);
482 XBT_PUBLIC(int) gras_datadesc_cb_pop(gras_datadesc_type_t typedesc,
483 gras_cbps_t vars, void *data);
485 XBT_PUBLIC(void) gras_datadesc_cb_push_int(gras_datadesc_type_t typedesc,
486 gras_cbps_t vars, void *data);
487 XBT_PUBLIC(void) gras_datadesc_cb_push_uint(gras_datadesc_type_t typedesc,
488 gras_cbps_t vars, void *data);
489 XBT_PUBLIC(void) gras_datadesc_cb_push_lint(gras_datadesc_type_t typedesc,
490 gras_cbps_t vars, void *data);
491 XBT_PUBLIC(void) gras_datadesc_cb_push_ulint(gras_datadesc_type_t typedesc,
492 gras_cbps_t vars, void *data);
494 XBT_PUBLIC(void) gras_datadesc_cb_push_int_mult(gras_datadesc_type_t
495 typedesc, gras_cbps_t vars,
497 XBT_PUBLIC(void) gras_datadesc_cb_push_uint_mult(gras_datadesc_type_t
501 XBT_PUBLIC(void) gras_datadesc_cb_push_lint_mult(gras_datadesc_type_t
505 XBT_PUBLIC(void) gras_datadesc_cb_push_ulint_mult(gras_datadesc_type_t
513 /** @defgroup GRAS_dd_cb_full Data description with Callback Persistant State: Full featured interface
516 * Sometimes, one of the callbacks need to leave information for the next
517 * ones. If the simple push/pop mechanism introduced in previous section
518 * isn't enough, you can always use this full featured one. The bad point is
519 * that it is quite badly documented...
521 * \htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Full featured Callback State" -->\endhtmlonly
527 XBT_PUBLIC(void) gras_cbps_v_pop(gras_cbps_t ps, const char *name,
528 /* OUT */ gras_datadesc_type_t * ddt,
529 /* OUT */ void **res);
530 XBT_PUBLIC(void) gras_cbps_v_push(gras_cbps_t ps,
532 void *data, gras_datadesc_type_t ddt);
533 XBT_PUBLIC(void) gras_cbps_v_set(gras_cbps_t ps,
535 void *data, gras_datadesc_type_t ddt);
537 XBT_PUBLIC(void *) gras_cbps_v_get(gras_cbps_t ps, const char *name,
538 /* OUT */ gras_datadesc_type_t * ddt);
540 XBT_PUBLIC(void) gras_cbps_block_begin(gras_cbps_t ps);
541 XBT_PUBLIC(void) gras_cbps_block_end(gras_cbps_t ps);
547 /*******************************
548 **** About data convertion ****
549 *******************************/
550 XBT_PUBLIC(int) gras_arch_selfid(void); /* ID of this arch */
553 /*****************************
554 **** NWS datadescription * FIXME: obsolete?
555 *****************************/
558 * Basic types we can embeed in DataDescriptors.
561 { CHAR_TYPE, DOUBLE_TYPE, FLOAT_TYPE, INT_TYPE, LONG_TYPE, SHORT_TYPE,
562 UNSIGNED_INT_TYPE, UNSIGNED_LONG_TYPE, UNSIGNED_SHORT_TYPE, STRUCT_TYPE
564 #define SIMPLE_TYPE_COUNT 9
566 /** \brief Describe a collection of data.
568 ** A description of a collection of \a type data. \a repetitions is used only
569 ** for arrays; it contains the number of elements. \a offset is used only for
570 ** struct members in host format; it contains the offset of the member from the
571 ** beginning of the struct, taking into account internal padding added by the
572 ** compiler for alignment purposes. \a members, \a length, and \a tailPadding are
573 ** used only for STRUCT_TYPE data; the \a length -long array \a members describes
574 ** the members of the nested struct, and \a tailPadding indicates how many
575 ** padding bytes the compiler adds to the end of the structure.
578 typedef struct DataDescriptorStruct {
582 /*@null@ */ struct DataDescriptorStruct *members;
586 /** DataDescriptor for an array */
587 #define SIMPLE_DATA(type,repetitions) \
588 {type, repetitions, 0, NULL, 0, 0}
589 /** DataDescriptor for an structure member */
590 #define SIMPLE_MEMBER(type,repetitions,offset) \
591 {type, repetitions, offset, NULL, 0, 0}
592 /** DataDescriptor for padding bytes */
593 #define PAD_BYTES(structType,lastMember,memberType,repetitions) \
594 sizeof(structType) - offsetof(structType, lastMember) - \
595 sizeof(memberType) * repetitions
597 XBT_PUBLIC(gras_datadesc_type_t)
598 gras_datadesc_import_nws(const char *name,
599 const DataDescriptor * desc,
600 unsigned long howmany);
604 #endif /* GRAS_DATADESC_H */